mercurial/node.py
author Yuya Nishihara <yuya@tcha.org>
Sun, 17 May 2015 15:16:13 +0900
changeset 25344 ceaf04bb14ff
parent 10263 25e572394f5c
child 25737 1a5211f2f87f
permissions -rw-r--r--
revset: add fast path for _list() of integer revisions This can greatly speed up chained 'or' of integer revisions. 1) reduce nesting of chained 'or' operations 2) optimize to a list 3) fast path for integer revisions (this patch) revset #0: 0 + 1 + 2 + ... + 1000 1) wall 0.483341 comb 0.480000 user 0.480000 sys 0.000000 (best of 20) 2) wall 0.025393 comb 0.020000 user 0.020000 sys 0.000000 (best of 107) 3) wall 0.008371 comb 0.000000 user 0.000000 sys 0.000000 (best of 317) revset #1: sort(0 + 1 + 2 + ... + 1000) 1) wall 0.035240 comb 0.040000 user 0.040000 sys 0.000000 (best of 100) 2) wall 0.026432 comb 0.030000 user 0.030000 sys 0.000000 (best of 102) 3) wall 0.008418 comb 0.000000 user 0.000000 sys 0.000000 (best of 322) revset #2: first(0 + 1 + 2 + ... + 1000) 1) wall 0.028949 comb 0.030000 user 0.030000 sys 0.000000 (best of 100) 2) wall 0.025503 comb 0.030000 user 0.030000 sys 0.000000 (best of 106) 3) wall 0.008423 comb 0.010000 user 0.010000 sys 0.000000 (best of 319) But I admit that it is still slower than the spanset. revset #3: 0:1000 3) wall 0.000132 comb 0.000000 user 0.000000 sys 0.000000 (best of 19010)

# node.py - basic nodeid manipulation for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import binascii

nullrev = -1
nullid = "\0" * 20

# This ugly style has a noticeable effect in manifest parsing
hex = binascii.hexlify
bin = binascii.unhexlify

def short(node):
    return hex(node[:6])